Add README, new_cycle, weekly_review, and update habits.sh

habits.sh

@@ -19,41 +19,79 @@ ensure_file() {
   touch "$HABITS_FILE"
 }
 
+date_add_days() {
+  local day="$1" offset="$2" date_arg epoch
+
+  date_arg="$day $offset days"
+  if date -d "$date_arg" +%F >/dev/null 2>&1; then
+    date -d "$date_arg" +%F
+    return
+  fi
+
+  # BSD/macOS date. Parse at noon to avoid midnight DST edges.
+  epoch="$(date -j -f '%F %H:%M:%S' "$day 12:00:00" +%s)"
+  epoch=$((epoch + offset * 86400))
+  date -r "$epoch" +%F
+}
+
 open_habits() {
   ensure_file
   "${EDITOR:-vi}" "$HABITS_FILE"
 }
 
+print_day() {
+  local day="$1"
+
+  printf '# %s\n\n' "$day"
+  printf '## Habits\n\n'
+  while IFS= read -r habit; do
+    [ -n "$habit" ] && printf -- '- [ ] %s\n' "$habit"
+  done <<< "$HABITS"
+  printf '\n## Metrics \n\n'
+  while IFS= read -r metric; do
+    [ -n "$metric" ] && printf -- '- %s\n' "$metric:"
+  done <<< "$METRICS"
+  printf '\n'
+}
+
 new_day() {
   ensure_file
 
-  local date
-  date="$(date +%F)"
+  local today latest start day tmp added
+  today="$(date +%F)"
+  latest="$(grep -E '^# [0-9]{4}-[0-9]{2}-[0-9]{2}$' "$HABITS_FILE" | sed 's/^# //' | sort | tail -n 1 || true)"
 
-  if grep -q "^# $date$" "$HABITS_FILE"; then
-    echo "A habits entry for $date already exists: $HABITS_FILE" >&2
+  if [ -n "$latest" ] && [[ "$latest" > "$today" ]]; then
+    echo "Latest habits entry is in the future: $latest" >&2
     exit 1
   fi
 
-  local tmp
+  if [ "$latest" = "$today" ]; then
+    echo "Habits entries already exist through $today: $HABITS_FILE"
+    return
+  fi
+
+  if [ -n "$latest" ]; then
+    start="$(date_add_days "$latest" 1)"
+  else
+    start="$today"
+  fi
+
   tmp="$(mktemp)"
+  added=0
 
   {
-    printf '# %s\n\n' "$date"
-    printf '## Habits\n\n'
-    while IFS= read -r habit; do
-      [ -n "$habit" ] && printf -- '- [ ] %s\n' "$habit"
-    done <<< "$HABITS"
-    printf '\n## Metrics \n\n'
-    while IFS= read -r metric; do
-      [ -n "$metric" ] && printf -- '- %s\n' "$metric" ":"
-    done <<< "$METRICS"
-    printf '\n'
+    day="$today"
+    while [[ "$day" > "$start" || "$day" = "$start" ]]; do
+      print_day "$day"
+      added=$((added + 1))
+      day="$(date_add_days "$day" -1)"
+    done
     cat "$HABITS_FILE"
   } > "$tmp"
 
   mv "$tmp" "$HABITS_FILE"
-  echo "Added $date to $HABITS_FILE"
+  echo "Added $added habits entr$( [ "$added" -eq 1 ] && printf 'y' || printf 'ies' ) through $today to $HABITS_FILE"
 }
 
 remaining_habits() {
@@ -80,6 +118,7 @@ case "${1:-}" in
     ;;
   new)
     new_day
+    open_habits
     ;;
   left)
     remaining_habits